Printing plate clamp operating means



4,1934. o. c. RoEsEN I l PRINTING PLATE CLAMP OPERATING MEANS Filed Deb. 1e, 195o Patented Dec. 4, 1934 A UNITED STATES PATENT OFFICE PRINTING PLATE CLAMP OPERATING MEANS Application December 18, 1930, Serial No. 503,208

9 Claims.

This invention relates to a means for operating printing plate clamps on the printingcylin` der of a press.

The principal objects of the invention are to provide power-operated means for releasing the clamp so that all the plates on a section of the cylinder will be loosened at the same time and ready for removal and so that the operator will have nothing to do but start the power-clampoperating mechanism to secure the locking of the plates after they 'are placed in position or their unlocking.

Other objects and advantages of the invention will appear hereinafter.

Reference is to be had to the accompanying drawing, vin which Fig. 1 is a side view of a printing plate cylin-` der and associated parts with the clamping means shown in radial section, illustrating a preferred embodiment of this invention;

Fig. 2 is a sectional view on the line'2-2 of Fig. 1, showing the cylinder and cooperating parts in end elevation, and

Fig. 3 is a view partially in section showing a modification of the power-operating mechanism. In putting printing plates on a press, theusual custom is to lock them up by clamps which are operated with a screw and necessitate the placing on of a wrench by the operator for pulling the clamps up tight. This invention relates to clamps which are spring pressed into locking position.

The plate cylinder 10 is provided with anend clamp 11 mounted in longitudinal slots 12 at the H end of the plate cylinder. Each clamp 11 is provided with two or more rods 13 extending inwardly longitudinally of the cylinder and xed tc the clamp between a shoulder on the rod and a nut on the extreme outer end of the rod. This rod is provided with a collar 14 xed to it and between this collar and a shoulder in` a recess 15 in the cylinder, through which the rod passes, is mounted a spring 16. This spring therefore returns the plate clamp to its locked position, where a bevel surface 17 on the plate clamp engages the edge of the plate P, and holds it there.

Preferably two such rods and springs are employed for each clamp. It is well understood that each clamp extends substantially around half of the end of the cylinder so that the cylinder can be turned to two positions diametrically opposite each other for removing and replacing the plates. However, any desired number of .55 these rods can be used on each plate. Of course,

there are clamps at the other end of the cylinder for,` the same purpose. l

Thev endplates are held in position between surfaces 17 and similar surfaces onthe slidable center clip 18. This lcenter clip also holds the ends of the center plates P'. Each rod 13 passes y leased the outer end of the plate P so that both plates are fully released.

The'end clamp 11- carries two projections 2l which extend beyond the end of the plate cylin- 4 der and are perforated for the mounting of a shaft 22. By this shaft a lever 23 is pivotally connected with the clamp. It is also pivotally mounted on brackets 24 mounted on the end of the plate cylinder. Thev opposite end of the lever 23 is bifurcated andv carries a shaft 26 on which is a cam roll 25.

`It will be seen therefore that when the parts are in the position shown in Fig. 1 the springs 16 pull the end clip in and clamp both plates P andI P'. It also draws in the shaft 26 and cam roller On the outside of the press frame F is mounted a motor 27 carrying a pinion 28 on its shaft. This pinion, through a gear 29 and a worm 30, integral therewith preferably, rotates a worm wheel 31. This Worm wheel has an internal thread cooperating with screw-threads on a reciprocable push rod 32 carried by the frame. This push rod is slidingly keyed so that it cannot turn. Therefore the operation of the motor will move this rod longitudinally in one direction or the other. A bracket 33 is fixed on the frame and acts as a guide for the push rod 32 and also to prevent side movement of the Worm wheel 3l. The push rod 32 has a head 34 on the inner end.V

When it is desired to unlock the plates on the press, the press isy stopped at a plating position and the motor is connected with the line so that push rod 32 to the left. The head 34 engages the cam roll 25, pushing it to the left and consequently pulling the end clamp 11 to the right, resisted by the springs 16. When the operator has finished his plating he connects the motor in the reverse direction, which withdraws the push rod and again allows the springs to relock the plates.

It will be observed that at the end of each it will rotate the `train of gears to move the ,100

cylinder carrying semi-cylindrical printing plates as usual there are two plating positions diametrically opposite. This one operating mechanism serves for both.

In Fig. 3 is shown a. modicationof the operating mechanism to be used in connection with the locking mechanism, the same as shown in Fig. 1. In this case the force required for unlocking the plates is supplied by a cylinder 40 and piston 41. is admitted through a valve 42Y to force/a the piston to the left. The rod 43 of this piston-.is the equivalent of the rod 32 kin the other case. The valve 42 is a well known typepijvalvel arranged so that rotation in one direction admits live pressure to one side of the piston and rotation of the valve in the opposite direction notI only cuts on the live pressure butppenathe mechanism is independent oi the cylinderandA .so located that, when the cylinder is movedto either of its two opposite positions for plating, the cam roll 25 will be in position to be operated by the head of the push rod. The plates are all released automatically and the clamps kept unlocked until the new plates are put on and then the operating means is withdrawn so thatthe springs will relock the plates. Y l

Although I have illustrated and described only two forms ofthe invention I am awareof the act that niodiiications may be madethereinby from the scope of the invention as expressed in the claims. Therefore I do not- Wish to be limited in this respect but whatI do claim is2f- 1. In a device for operating a plate clampon a cylinder of a printing press, the combination oi a rod mounted on the frame of thev press, power-operated means for moving the rod longitudinally toward and from the cylinder and means supportedby the cylinder and separate from the clamp adapted to be engaged by said rod for withdrawing the plate clamp. M

2. The combination with a printing press plate clamp and yielding means for holding :it in f clamped position against the plates,A of l,poweroperated means for forcing the clamp back to` unlock the plate comprising a rod movable .y

toward the cylinder and a lever; pivoted tothe cylinder and having one end invposition tobe engaged by said rod and the other end connected with the plate clamp.

3. In a device for operating a plate clamp onZ a cylinder of a printing press, the combinationv of -a rod mounted on-the frame of Vthe press, power-operated means for movingthe rod longitudinally toward and from the cylinder, means supported by the cylinder and independent of.Y

the plate clampk adapted to be engaged and operated by said rod for withdrawing the plate .y

Air or other iluid under pressure' position.

,.cylinder. any person skilled in the art without` departing clamp, and yielding means carried by the cylin der for returning the clamp to clamping position when the rod is moved away from the cylinder.

4.Ina device for operating` a plate. clamp, theycombinationfpf a motor, al `worm wheel operated by said motor and "threaded internally and centrally,I a rod having a screw-thread meshing with the threads in the worm wheel mounted on the frame to reciprocate, said rod having a.head,.a.lever carried by the plate cylfinder and having a cam roll at one end in position,r wh,en the cylinder is in plating position,

the plate 'clamp to Withdraw it from clamping 5.L Inyajdevice for operating a plate clamp, the combination of a rod mounted on the frame of the machine and having a head for operating u the .plate .-.C1s1`r1py a; piston 1.0m, the Othelend 0f the rod, `a cylinder in which, the piston is located, means for introducing nuidunder presating the plate clamp and a springwfor moving the kpiston back when the iluid behind it is exhusted.k v f 6. In aplate c lainp for a printing cylinder, the

`vrsure for moving the rod into vposition for opery combination With the ,cylindervhaving a longi-f,v

tudinal recess,an end clamp,`- anda slidable cen! ter clip, oi a rod in said recess, a compression springen the rod toxhold the rod vyieldingly in plate locking position the rod `having means for unclamping vthe center.I clipV after the end,t

clamp moves to unclamp the the combination with` they cylinder havingv a end plate on the longitudinal recess, an end clamp, and a slid-..

able center` clip, of a rod in said recess, *a *springl on-l the rod, one end of the spring engaging a fixed part of the cylinder, a collar on the rod which is-engaged bythe other end of the .spring v'to-hold thevr'odyieldingly inplate locking position,the end clampv being `fixed'to the-rod, the rod being slidably Iconnected te the center clip and having means for unclamping -`the center clipvafter the-end clamp moves to unclamp the endplate,QnthecyIinder. y. y

8. Inga,y printing plate lock up, the combination of an end plate clamp, a movable center clip, arod Yslidably. connected with `thecenter clip andxedto the end clamp,-and a compression spring on the rod for forcing the end clamp into locking position, for the purpose described.

l 9. The combination with a plate clamp fora printing platecylinderand yielding means for holdingv it in, and returning it to, clamped position, of. means mounted on thek cylinder and .movable independent of the plate clamp for 

